mddiff(1)						 Sync Mail Dir (smd) documentation						 mddiff(1)

NAME

       mddiff - computes diff for maildirs

SYNOPSIS

       mddiff [--max-mailno mno] [--db-file dbf] [-l|--list] [-s|--symlink]
	      [--exclude globexpr] [-v|--verbose] [-d|--dry-run]
	      [-n|--no-delete] [--help] [--sha1sum] paths

DESCRIPTION

       mddiff  computes  the delta from an old status of a maildir (previously recorded in a support file, called db file) and the current status,
       generating a set of commands (a diff) that a third party software can apply to synchronize a (eventually remote) copy of the maildir.

       If paths is a single file name, and that file is a fifo, mddiff reads from it file names separated by new line and outputs the sha1 of  its
       header and body separated by space.

	     $ mddiff /tmp/fifo_for_mddiff
	     806a0ffe4f29766effd764... 463e543da9dac8e298...
	     582cbb6a5cd3ce13965c8c... 8fa60a7458b1157193...
	     ...

       If  paths  is  a  single  file name, and that file is a fifo, and the -s option is passed, mddiff reads from that fifo two lines at a time,
       respectively a source name and a target name. It then creates a symlink named as as the target name pointing to the source  name.  If  some
       dictories  need	to  be	created  in  order to create the symlink, this is also done. mddiff will print 'OK' on stdout to signal a success,
       'ERROR' to signal an error.

       If paths is a list of directories, mddiff outputs a list of actions a client has to perform to synchronize a copy  of  the  same  maildirs.
       This  set  of  actions  is  relative to a previous status of the maildir stored in the db file.	The input directories are traversed recur-
       sively, and every file encountered inside directories named cur/ and new/ is a potential mail  message  (if  it	contains  no  

  it	is
       skipped).

	     $ mddiff ~/Mail/
	     ADD ~/Mail/cur/1239038050.14937_1.garfield:2,S 66532ebb05b252e...
	     ...

       Every  client (endpoint using mddiff for synchronization) must use a different db-file, and the db-file is strictly related with the set of
       directories given as arguments, and should not be used with a different directory set. Adding items to the directory  set  is  safe,  while
       removing them may not do what you want (delete actions are generated).

       mddiff  does  not  alter  the  dbf  file, it generates a new one called dbf.new.  It is up to the higher level tool smd-server(1) to rename
       dbf.new to dbf in case the other endpoint successfully applied the diff.

       The --exclude option tells mddiff to ignore all paths matching the given glob(7) expression. This option  can  be  passed  multiple  times.
       Matching  is  performed	using  fnmatch(3) with no special flags, thus '*' and '?' match any character including '/'. Matching is performed
       when a directory is entered. If the match is successful, the directory and all its subedirectories are skipped.

       The --no-delete option tells mddiff to not output a DELETE action for files that disappear. Note that a DELETE action is  anyway  generated
       for files that are moved (i.e. move is COPY plus DELETE). The result is that deletions are not propagated to the other endpoint.

OPTIONS

       --max-mailno mno
	      Estimation  of  max mail message number (defaults to the number of messages in the db-file + 1000 or 500000 if there is no db-file).
	      You may want to decrease it for the first run on small systems. It is anyway increased automatically when needed

       --db-file dbf
	      Name of the cache for the endpoint (default db.txt)

       --exclude globexpr
	      Exclude paths maching the given expression

       --sha1sum
	      Behaves like the sha1sum utility

       --mkdir-p
	      Behaves like mkdir -p

       --mkfifo
	      Behaves like mkfifo

       -l --list
	      Only list the mailboxes recursively contained in paths

       -s --symlink
	      Create symlinks for paths read on the input fifo

       -v --verbose
	      Increase program verbosity (printed on stderr)

       -d --dry-run
	      Do not generate a new db-file

       -n --no-delete
	      Do not track deleted files

       --help This help screen

NOTES

       mddiff is a low level utility, used by smd-server and smd-client. You should use higher level tools like smd-pull(1), smd-push(1) and  smd-
       loop(1)

SEE ALSO

       smd-client(1), smd-server(1), smd-pull(1), smd-push(1), smd-loop(1)

AUTHOR

       Enrico Tassi <gares@fettunta.org>

								   11 June 2012 							 mddiff(1)